Description: The lapse rate describes the rate at which air cools with altitude. Atmospheric stability depends on the lapse rate. When an air parcel is lifted or lowered, it can continue to rise or descend based on the temperature of the surrounding air at the new altitude, which indicates an unstable atmosphere. Inversions can occur in the atmosphere, meaning the air near the ground will be cooler than air aloft. This type of temperature profile can cause air to be trapped near the Earth's surface in a boundary layer, which can also lead to pollutants being trapped near the ground.